also jackrabbit, large prairie hare, 1863, American English, shortening of jackass-rabbit (1851; see jackass + rabbit (n.)); so called for its long ears. Proverbial for bursts of speed (up to 45 mph).
jack-hammer
jack-in-the-box
jack-knife
Jack-o'-lantern
jackpot
jack-rabbit
jacks
jack-shit
Jacksonian
jackstraw
Jacob
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